CVE-2019-20888 : Security Advisory and Response

A vulnerability has been identified in Mattermost Server versions prior to 5.7, 5.6.3, 5.5.2, and 4.10.5, allowing attackers to initiate a denial of service attack by consuming excessive memory through outgoing webhooks or slash command integrations.

Understanding CVE-2019-20888

This CVE refers to a vulnerability in Mattermost Server that could lead to a denial of service attack.

What is CVE-2019-20888?

CVE-2019-20888 is a vulnerability in Mattermost Server versions before 5.7, 5.6.3, 5.5.2, and 4.10.5, enabling attackers to exhaust memory resources by leveraging outgoing webhooks or slash command integrations.

The Impact of CVE-2019-20888

The vulnerability allows malicious actors to disrupt server operations by causing excessive memory consumption, potentially leading to service unavailability.

Technical Details of CVE-2019-20888

This section provides technical insights into the vulnerability.

Vulnerability Description

The issue in Mattermost Server versions prior to 5.7, 5.6.3, 5.5.2, and 4.10.5 permits attackers to execute a denial of service attack through memory consumption via outgoing webhooks or slash command integrations.

Affected Systems and Versions

Mattermost Server versions before 5.7, 5.6.3, 5.5.2, and 4.10.5

Exploitation Mechanism

Attackers can exploit this vulnerability by sending malicious requests through outgoing webhooks or slash command integrations, causing the server to consume excessive memory.

Mitigation and Prevention

Protecting systems from CVE-2019-20888 requires immediate actions and long-term security measures.

Immediate Steps to Take

Update Mattermost Server to versions 5.7 or newer to mitigate the vulnerability
Monitor server memory consumption for unusual spikes

Long-Term Security Practices

Regularly update software to the latest versions
Implement network and application-level security controls

Patching and Updates

Apply patches provided by Mattermost to address the vulnerability